Surviving the Extremes: A Doctor's Journey to the Limits of Human Endurance (29 page)

We not only know very little about life in the sea, we know very little about the sea itself. Huge currents flow between and around the continents, currents of which we have only the vaguest awareness, even though they largely determine our climate and weather patterns. The most-studied of those currents, the Gulf Stream, brings heated equatorial water northward across the Atlantic, where it warms the European continent. How effectively it does that is readily apparent when you consider that the French Riviera and Nova Scotia, Canada, are at the same latitude. In the 1970s, an enormous lake of cool fresh water appeared just below the surface of the North Atlantic, probably the result of an ice melt off the coast of Greenland. The water chilled the Gulf Stream for several years—years that corresponded to some of the coldest winters Europe has known. When the lake finally dissipated, the balmier weather returned.

In a highly ambitious attempt to learn more about what is going on in the sea—and who and what might be living there—plans are under way to construct an international subsurface research station that will drift around the world for two years on the great ocean currents. The 120-foot-tall aluminum station, named
SeaOrbiter,
will resemble a boat bobbing vertically in the water. The upper half will provide a platform for atmospheric measurements and satellite communications;
the lower half will constitute a continuous undersea laboratory for studying the biology, chemistry, and physics of the ocean. The station projects 50 feet below the surface, with a panoramic window near the bottom from which to observe strange sea life—not the least of which will be the saturation divers who will come and go from the hyperbaric chamber on the lowest deck. Six divers will remain permanently in saturation for each leg of the voyage, giving them quick, easy, and anytime access to the environment while also, not incidentally, providing models for studying the effects of prolonged saturation.

As a member of
SeaOrbiter’s
scientific committee, I have discussed the project at length with its chief architect, Jacques Rougerie, and met with many of the researchers and engineers. As a member of
SeaOrbiter
’s crew when it is cast adrift, I will be at one frontier of the sea, helping to probe its deepest mysteries. Even at its deepest point, the ocean’s bottom will always be less than 7 miles below our research station. Yet the sea remains the least explored, least understood environment on earth because it is the most hostile to man. The environment from which all life arose and on which all life still depends has become, to humans, through the nearly imperceptible small steps of evolution, the most extreme environment on earth.

HALF A BOWL OF WARM WATER
is not much to eat, but at midnight in a tent at 26,000 feet, I was happy to have even that. One of three climbers crammed into a two-man tent, I was trying to rest but the temperature
inside
the tent was 30°F below zero, and it was frightening to think how much colder it must be outside. The weather was holding, though; we couldn’t let a good chance like this go by. After two months in this hostile environment, we were dehydrated, malnourished, oxygen-starved, and exhausted, but if our bodies could hold out another sixteen to twenty hours, we could reach the highest point on earth.

There were nine of us in the three tents we pitched on the South Col, 3,000 feet below Mount Everest’s 29,035-foot summit. These altitudes are the domains of jumbo jets cruising high over the oceans, not creatures born and raised near sea level. Our bodies were deteriorating rapidly, consuming themselves to produce enough energy to function in a world with hardly any heat or air pressure. Though our expedition had arrived at this camp only six hours before, after days of relentless climbing, it was already time to move on. Too prolonged a stay could become a permanent one.

I took off my oxygen mask, disconnecting myself from the bulky tank lying on the floor, unzipped the door flap, and crawled out of my thin nylon shelter. The sky was black except for a sharp silver moon, two-thirds full, beaming just enough light to make the ice all
around us glow deep blue. The still air was actually not much colder than it had been inside the tent. So effective were our insulated clothing and sleeping bags at retaining body heat that little had escaped to warm the interior of the tent. Insulation only conserves heat, however; it doesn’t produce it. To do that, the body needs to burn fuel. Burning fuel requires oxygen, and now that I was separated from my supplemental supply, my body would have to make do with what it found in the air around it, which is about one-third the amount at sea level.

My breathing turned deeper and more rapid and my pulse quickened as I put on my climbing gear. Some of this was due to nerves—I was about to attempt the summit of Mount Everest—but most of it was my body’s automatic response to the lack of oxygen. My lungs were working harder to drive more air inside, and my heart was beating faster to pump the limited oxygen supply to where it was most needed. Even so, I was feeling much colder by the time I had buckled my harness and hoisted my pack. Though the outside temperature hadn’t changed, my body’s ability to cope with it had. Without the extra oxygen, my internal combustion was slowing. Fuel can’t provide energy when there isn’t enough oxygen to burn it. My metabolism was becoming a smoldering fire too weak to generate enough heat to keep me warm.

A group of fragile humans were about to set off on a journey through a dark, frozen, air-depleted, and lifeless portion of the planet, our survival dependent upon the life-support system we were bringing with us: lights, clothes, food, water, and oxygen. We would be under attack every step of the way. All we could do was hope that our portable minienvironment would keep our bodies from realizing where they really were.

The first line of defense is clothing. Mine consisted of three layers: next to my skin, polypropylene underwear—to keep me warm while wicking away the sweat that would otherwise accumulate on my skin and dissipate my body heat thirty times faster than if my skin were dry; next, a one-piece suit made of down—a goose’s soft under feathers designed by nature into a pattern that creates millions of tiny heat-retaining air pockets; my outer layer was a nylon shell—to act as
a windbreaker and to keep my inner layers dry despite constant contact with ice and snow.

Heat loss is greatest at the body’s “ends”—head, hands, and feet—where surface area is large in comparison with the volume of tissue inside. I wore a tight-knit wool hat with a balaclava tucked inside—a wool ski mask that could be folded down to cover my face and neck, leaving only slits for my eyes, nose, and mouth. My eyes were covered by goggles to block the wind and the ultraviolet radiation, my nose and mouth covered by an oxygen mask.

Keeping hands warm remains an unsolved problem in mountaineering. Fingers, being long thin appendages, are very vulnerable to freezing. Protecting them requires heavy insulation, but gloves frustrate the dexterity a climber needs. No glove will keep a hand warm if it isn’t worn. The compromise usually consists of two pairs of gloves: a thin, conforming inner pair covered by an outer bulkier mitten—not having finger separations, mittens have greatly reduced surface area and thus retain much more warmth. For tasks that require individual fingers, the mittens are removed and left dangling from little strings attached to the jacket sleeves (the way toddlers wear them) so they won’t blow away in the wind. It sounds fine in theory, but in practice mittens are annoying, and they are off far more often than they should be.

Feet are easier to insulate than hands because toes are stubbier than fingers and don’t have to move independently. Two pairs of socks—one polypropylene, one wool—enclosed in plastic double boots can amply protect them. A metal platform with spikes—a crampon—is attached to the sole of each boot to grip the ice. Though metal is a rapid conductor of heat, and the crampon is in nearly constant contact with snow or ice, the double boot, with its layer of trapped air, acts like a thermos to keep body heat inside.

Even perfect insulation won’t protect a body that’s not generating heat. As we stood around checking our gear, our own as well as each other’s, then waited for everyone to make last-minute adjustments to satisfy themselves that they were absolutely ready, the relative inactivity caused me to shiver—not in anticipation of what lay ahead, but because my body temperature had dropped far enough to alarm the
thermostat in my hypothalamus. It signaled my muscles to shake in order to produce heat. My body was stoking its internal fire.

The fire would burn a lot hotter once we were under way. The large muscles in my arms and legs would begin working, providing the heat to rewarm my body as well as the power to carry me, I hoped, to the summit and then back. The round-trip, however, would require a great deal of oxygen, fuel, and water, all of which were in limited supply. My backpack contained two lightweight oxygen cylinders and a few chocolate bars. A bottle of hot water was tucked inside my down suit to keep it warm. We had to be self-contained and self-sufficient. There would be no food and, since we had neither the fuel nor the time to melt snow, no water. Most dangerous of all, there would be not nearly enough air.

I turned on my regulator, set it for a rate of 2 liters per minute, and made sure there were no kinks in the hose that directed the oxygen flow from the backpack and wound under my arm and up to my nose and mouth. I slipped the mask over my head and cinched the straps to create an airtight seal against my face. After a few reassuring breaths of oxygen, I lowered my goggles into place, turned on my headlight, and took my first steps toward the summit of Mount Everest.

We left Camp IV, the encampment on the South Col, with high hopes and strong determination. None of us would have gotten this far without plenty of both. Sheer will can take you deep into an inhospitable environment, but you still have to bring your body along, and though the day was just starting, our bodies were already fast approaching their limits. We had been moving up and down the mountain for two months, burning vast quantities of energy without replenishing the fuel supply adequately. High altitude blunts sensations of hunger and thirst. If things went well, I would need to burn 12,000 to 15,000 calories on this day—ten times what the body uses in an average day—and maybe more than I had in reserve.

The route to Everest’s summit starts out across the Col, a broad, flat ice sheet that ends in a snow gully. In the darkness, our expedition became a procession of lights, each climber a yellow dot against the deep blue of the ice. The air was cold but my high rate of activity, sustained by the steady flow of oxygen, was enough to warm my body.
No wind broke the silence. I listened to the rhythm of ice crunching under my crampons and oxygen flowing in and out of my lungs.

We entered the snow gully, which first gradually and then quickly steepened into what is known as the Triangular Face. Our line of lights became more vertical, the spacing more irregular as each climber progressed at his or her own rate. As I moved up the Face, the headlight in front of me came steadily nearer. The climber seemed to be losing power early. Finally, his headlight stopped. My light soon illuminated the back of a heavy down jacket—and the cause of the climber’s exhaustion. He was overdressed. He had been working strenuously enough to overheat despite an outside temperature lower than 30°F below zero.

The diagnosis was easy—though heat exhaustion is not one of the illnesses you think of first when you consider the risks of high-altitude climbing. The treatment was easy too: take his jacket off and let the cold air catch up with him. But nothing is simple near the summit of Mount Everest. The snow we had been climbing through was too powdery to kick steps into, and we had been relying primarily on our hands for support, not trusting our footholds. To free our hands in order to remove the climber’s jacket, we would have to shift all our weight to our feet, and we weren’t sure the snow would hold. Other climbers came up behind me, and we worked out a treatment plan. I was the expedition’s doctor but far from its most skilled climber. I had prescribed the appropriate treatment based upon my diagnosis, but that treatment would be carried out by two of my stronger teammates as I moved up the slope a bit more to watch. They placed an ice screw in the snow above them, fed a rope through it, then hooked it to their harnesses. Hanging from the rope—to which they also attached the heat-exhausted climber—they could keep their hands free to work off his jacket. Once it was removed, the climber revived dramatically in the cold air, so much so that he soon passed me as we all continued upward.

With the delay, the line of lights was now fairly high above me. I tried to quicken my pace to catch up but didn’t have enough oxygen. Reaching a crest in the Triangular Face, I was momentarily relieved to see that the route became less steep and that the others weren’t too
far ahead. As I crossed the crest, however, I immediately realized why the others hadn’t progressed farther than they had: I plunged into much deeper, drier snow. This would require more energy and more time to go less distance as well as more oxygen to sustain the extra effort. With higher steps and heavier breathing, we made our way toward the top of the Triangular Face. Our regulators were set on “continuous flow,” not “demand flow,” and since we had all dialed in the same rate—2 liters per minute—our first tanks would all be empty at about the same time. Some climbers were already stopping to change to their second tanks. My gauge indicated that my tank was nearly empty, but I wanted to use every ounce of oxygen I had, so I continued on toward a small rock outcropping that formed a flat spot in the slope. Two other climbers were there already, helping each other change tanks as I approached.